Comprehensive investigation of the mutual effect of Ce and W species in the NH₃-SCR catalyst

CeO2-WO3 catalysts were synthesized using the coprecipitation method (CW-C), mixing method (CW-M) and deposition-precipitation method (CW-DP). Among these, the CW-C catalyst exhibits exceptional denitration (deNO(x)) performance and N-2 selectivity, achieving over 90% deNO(x) efficiency and approximately 100% N-2 selectivity at 220-550 degrees C with a GHSV of 60 000 h(-1). Notably, its catalytic performance at low temperature has surpassed that of other catalysts significantly. This outstanding deNO(x) performance can be attributed to the intense mutual effect between CeO2 and WO3 and the formation of Ce-2(WO3)(3) species; a series of characterization studies reveal that CW-C has heightened redox properties and more surface acid sites, as well as the presence of Ce3+ species and chemisorption oxygen species (O-2(-)/O-). The reaction mechanism over the CW-C catalyst mainly follows the E-R mechanism, while CW-DP and CW-M mainly go through the L-H mechanism at temperatures below 350 degrees C.